Insulator



Jan. 30, 1923. 1,443,657

L. STEINBERGER. I NNNNNNN R H ED No F v. 23, l 917,

WITNESS:

g sri' /v ANU/ME Patented Jan. 30, 19x23.

'UNITED STATES PATENT OFFICE.

LOUIS STEINBERGER, OF BROOKLYN, NEW YORK.

' INSULATOR.

Application filed November 23, 1917. Serial No. 203,478.

of Brooklyn, county of Kings, city and Statev of New York, have invented certain new and useful Improvements in Insulators, of which the following is a specification. K

My invention relates to suspension lor strain type of insulators for high tension lines arranged in groups of two or more unit insulators per group, connected 1n series wlth each other, each unit insulator of a group having a different electro-static'capacity from the other unit or units of the group, whereby a more uniform distribution of the electrical tension 0r stress between the charged line and the support or tower for the group of insulators is secured.

One of the objects of my invention is to so construct the individual unit insulators'of a group and to so arrange these u nit insulators in series that a group of individual units will provide an insulator which" will have ability to withstand exceedingly high voltages.

Another object is to so construct the unit insulators of the group and to so grade them with respect to their electro-static capacities as to equalize the voltage distribution.

Another object is to save material and cost of construction and also to lessen the weight without decreasing the eiiciency.

Other objects will hereinafter appear from the subjoined specification and claims.

Referring to the drawings:

The figure is a vertical section of a group of insulators embodying my invention, the support being illustrated also in section and the line wire and clamp for securing the same to the lower insulator being shown in elevation. l

I have illustrated a type of any preferred form of disc insulator and of interlocking strain members embedded therein, which strain members areprovided with means well known in the art and which have been disclosed by me in my prior patents for securing -the one to the other, the construction of which is only necessary vto describe generally herein.

I provide a construction and-arrangement of grouped unit insulators whereby the electrostatic capacities of the individual insulators of a group diifer'from each other so as to secure a uniform distribution of the electrical stresses or strains to which the unit insulators of a group are subjected. The electrostatic capacities of the individual insulators of a groupare made to differ from each other by using electrical conducting rings or skirts in connection therewith of lvarying surface areas as more lfully de- The largest ring or skirt,

scribed below. or one having the largest surface area, is used. with the insulator of largest diameter which is placed next to the line wire, and the smallest ring or skirt is used with the insulator having the least diameter placed next to the support, and the intermediate insulaters with rings are graded accordingly thereby producing a gradation in electrost atic capacities of the individual insulators of a group from the one of largest diameter to that of the smallest diameter.

In a group of three insulators, such as shown in the drawing, theinsulator nearest the line wire has the greatest'diameter and the greatest electrostatic capacity. The insulator just above the -lowest insulator has a diameter and also an 'electro-static capacity greater respectively than the diameter and the electro-static capacity of the insulator justy above it, but less in each respect than those of the next lower insulator.

-lIy invention, however, isnot limited to a construction in which the insulators comprising the group have graded diameters only, for it may be applied to a series of unit insulators all of which have the same diameter. It is, however, necessary that the unit insulators have graded electro-static capacities, that is, the rings are graded with respect to their surface areas from line to support as above described.

I have used the word above in describing the invention when applied to a group of suspension insulators, as illustrated, but

it is tobe understood that the invention is. Yapplicable to a group of insulators when used as straininsulators, in which case each insulator may be situated in a horizontal relation to each other.

Referring to the figure of the drawing, l()V is 'a disc insulator and 11 and 12 the-respective .interlocking mechanical strain members;

from which they are suspended, or to Which they are secured by any suitable holding means as illustrated at 14. 15 is a line Wire and 15 a conventional clamp by means of "whlch the wire 1s secured to the lowerlnost strain member.

In constructing my invention I partially embed a metallic ring in the periphery of each of the disc insulators during the molding thereof.

By embedding rings of different surface areas in the different disc insulators vtheirl electrostatic capacities can be made to differ in the desired manner in accordance with the well-known fact that the surface area of a metallic element is a factor whichl governs lits electro-static capacity.

Then the insulators are of disc shape these metallic elements are ring shaped. The form of metal ring which is embedded in the peripheral edge of each of the insulators, which I have' found to be preferable surface area than that of the peripheral ring 16 of the insulator just above it, and the peripheral ring'16 is of greater surface area than that' of the peripheral ring 16 secured to the insulator immediately above it; so that the rings are graded with respect to their surface areas and by this construction they are graded with respect to their electro-static capacities. l t

While in 'thevdrawing the unit insulators as Well as the `metallic rings are of different diameters, it is to be understood that my invention is neither limited to the construction of insulators per se, nor of the metallic rings per se, but pertains to the particular grouping and grading in the respective unit insulators provided with metallic rings-constituting the group, as set forth herein.

When insulators are used which are provided with metallic rings as described and shown, the arcing will take place from the line to the ring. embedded in the insulator nearest the line, and from that ring to the ring embedded in the next unit, and from there to the next unit above, and so on throughout the units composing the group. By the arrangement described the metallic rings, together with the dielectric material consisting largely of air and partly of the insulating discs constitute a number of condensers of different electrostatic capacities connected in' series, the one of greatest electrostatic capacity being nearest the line.`

The electrostatic capacity to which reference is made in this connect-ion is the electrostatic capacity of each insulating unit between the strain members 1l and I13 due primarily to the capacity of the rings 16, 16', and 16"., when referred to a common ground or to zero potential. Since the potential across a condenser is directly proportional to its charge and inversely proportional to its capacity, it is desirable to have the capacities of the condensers nearer the line correspondingly larger than the capacities of those more remotely situated in order for the potentials across themvto be more nearly uniformly distributed so as to avoid throwing an excessive electrical stress on any single unit of the group. y

In addition toy the electrical value of the insulator provided with the projecting peripheral metallic rings, these rings also havefa mechanical function in that they will prevent the possible chipping of the peripheral edge of the insulator because of possible rough handling during shipment or transportation of the insulators. This function is, of course, incidental and in addition to the main purpose of the invention.

Any suitable insulating material may be used in making the structure described, but I prefer to use that particular insulating material known in the art as electrose within the scope of my invention, it is intended that all matter contained in the fabove description or shown in the accompanying drawings shall be interpreted as illustrative and not in a. limiting sense.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a device of the class described, a. series cf unit insulators each unit provided with strain members, s aid units being connected together to form a group, each unit having a single auxiliary metallic element connected thereto and insulated from the strain members,l said units being arranged in graded relation with respect to the electrostatic capacities of the auxiliary metallic elements, the least being nearest ground and the greatest nearest to the line, the remainder being graded accordingly.

2. In a device of the class described, a series of disc insulators each disc being provided With strain members said insulators being connected together by means of the strain members to form a group, each disc having .a single auxiliary metallic element embedded in its periphery, and insulated from the strain members and extending beyond said disc in a radial direction, said discs being arranged in graded relation with respect to the electrostatic capacities of the auxiliary metallic elements, the least nearest ground and the greatest nea-restL to the line. 3. In a device of the class described, a series of disc insulators each of which is provided with strain members said insulators being connected together by means of said strain members to form a group, each disc having asingle auxiliary annular` metallic element connected thereto and insulated from ,the .strain members, said disc insulators being arranged in graded relation With respect to the electrostatic capacities of the auxiliary annular metallic elements, the greater being next to the line and the lesser next to ground.

4. In a device of the class described, a group of unit insulators each unit being proi vided with strain members, andeach unit having a metallic ring embedded in its periphery and insulated from the stra-in members, said rings being graded with respect to the surface areas of said rings, the ring of least surface area being next to ground, yand the ring of greatest surface area being next to Vthe line, the intermediate rings being graded accor/dingly. y

5. In a device of the class described, a group of disc insulators each disc being provided With strain members and a peripheral ring of metal insulated therefrom, said rings being increasingly graded with respect to their electrostatic capacities from ground to line.

6. In a device fof the class described, a group of disc insulators, each disc being provided with strain members and a peripheral metal element molded therein and insulated from the said strain members, said insulators 'being increasingly graded with respect to the electrostatic capacities of ,the peripheral metallic elements from ground to line.

7. In a device of the class described, a group of unit insulators, each unit of the grouphavng strain members and a ring of metalpartially embedded in its periphery and insulated from the said strain members, the ring of metal in the unit next to the line havinga greater surface area than any one of the other rings.

8. In a device of the class described, a group of unit insulators, each unit of the group having strain members and a ring of metal partially embedded in its periphery and insulated from the said strain members, the ring of metal in the unit nextto the line other units of the group.

9. In a` device of the kind described, a

group of insulators consisting of two or more unit insulators secured together, each of said unit insulators having strain members and a .hood-shaped projecting metallic ring molded in its periphery and insulated from the strain members, the rin s being graded in electrostatic capacity, le least iext to ground and the greatest next to the I0. In a device of the. class described, a groupV of connected insulators each insulator of the group being provided with con* nectingvme'ans, the insulator at one end of the group being securedto a support, the insulator at the other 'end being secured to a line, the insulator secured to the support having a metal ring of a certain surface area partially embedded in its periphery, the

insulator' next 'thereto having a metal ring of largersurface area partially 'embedded in its periphery, and so on through the group, the insulator that is secured to the line having a metallic peripheral ring of the maximum surface area of any ring of the group` each of the rings being insulated from the connecting means of its insulator.

l1. In a device of the class described, a group of connected insulators each insulator of the group having connecting means secured thereto, the insulator at one end of the group being secured to a support, the insulator at the other end being secured toa line. the insulator secured tothe support having a metal ring of a certain electrostatic capacity, partially embedded in its periphery, the insulator next thereto having a metal ring of larger electrostatic capacity partially em? bedded in its periphery, and so on through the group, the insulator that is secured to the line having a metallic peripheral ring of the maximum electrostatic capacity of any ring of the group, each of the rings beingI insulated from the connecting means of its *insulator- Signed at the borough of Manhattamcity, county and State of New York, this 15th day of November, 1917.

LOUIS STEINBERGER( In presence of ISABEL R. RICHARDS, ZrrA M. GRAHAM, 

